All detergents on the market contain surfactants and builders. One of the most commonly used builders in phosphate-free detergents are alumninosilicates. They are inexpensive builders, which have as an additional benefit that they are easy to process. They are in fact useful process aids because they are very good structurants, binders or carrier materials for other detergent ingredients. Therefore, most detergents comprise a base powder made by spray-drying a slurry of aluminosilicate and surfactant or by agglomerating aluminosilicate and surfactant. Furthermore, aluminosilicates are useful as dusting agent, to reduce the stickiness or caking of the product.
A problem encountered with these detergents comprising a builder system containing aluminosilicates, it that they tend to cause fabric residues. These residues contain detergent products which is entrapped in the fabrics and/or are insoluble in water. They are noticeable by the consumer as spotting on the fabric.
Another problem encountered with, in particular solid, detergents is their tendency to gel upon contact with water. This leads to poor dispensing of the product from the dispensing drawer or from a dispensing device, and also to poor dissolution of the product into the wash water. This results in residues in the drawer, dispensing device, washing machine and on the fabrics, which may be noticeable as spots on the fabric. It has been found that in particular surfactants gel upon contact with water.
The inventors have now surprisingly found that this problems in particular arises when the surfactants and the aluminosilicates in the detergent are in close contact with one another, for example when they are in the detergent in an intimately mixture. This is for example the case in most known and used base powders, which are agglomerates or spray-dried powders containing. The inventors have now found that the residue formation problem but also the gelling problem or dissolution or dispensing problem mainly arises in most known products, when about all the anionic surfactants and aluminosilicates are intimately mixed with one another. When the degree of intimate mixing is reduced or even avoided completely, they have found that these problems are reduced or even solved completely.
Thus, the inventors have found a solution which still allows the incorporation of aluminosilicates and surfactants in detergent, but in a different manner: the invention provides thereto detergents comprising at least two components comprising the surfactants and the aluminosilicate in such a manner that a limited degree of intimate mixing occurs.
The detergents of the invention have a reduced fabric residue, in particular of insoluble detergent ingredients, gelling, an improved dispensing and dissolution. It has been found that these benefits are obtained by any convention way of introducing detergent to the wash, including by use of a dispensing drawer, a dispensing device or by addition of the detergent in the washing prior to addition of the wash load or addition of the detergent on top of the wash load.
The compositions may comprise an effervescence system to further aid the dispensing or dissolution or foaming.